 October 6, 2023
October 6, 2023
October 6, 2023
###### Programming-for-Output-Problems
October 6, 2023
 Question 754
Consider a file currently consisting of 50 blocks. Assume that the file control block and the index block is already in memory. If a block is added at the end (and the block information to be added is stored in memory), then how many disk I/O operations are required for indexed (single-level) allocation strategy?
 A 1 B 101 C 27 D 0
Question 754 Explanation:
Given data,
— Up time=75%
— Down time=25%
— How many times does this file server have to be replicated to give an Availability of at least 99% is=?
Option-A: Here 2 replications, it means down time is 25% equivalent 0.25.
According to 2 replications we have to multiply with 0.25*0.25=0.0625
Availability= 100-6.25%
= 93%
Option-B: Here 4 replications, it means down time is 25% equivalent 0.25.
According to 4 replications we have to multiply with 0.25*0.25*0.25*0.25
= 0.00390625
Availability= 100-0.0390625%
= 99.9609375%
Option-C: Here 8 replications, it means down time is 25% equivalent 0.25.
According to 8 replications we have to multiply with
= 0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25
= 0.0000152587890625
Availability= 100-0.00152587890625%
= 99.99847412109375%
Option-D: Here 16 replications, it means down time is 25% equivalent 0.25.
According to 16 replications we have to multiply with
= 0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25
= 0.00000000023283064365386962890625
Availability= 100-0.000000023283064365386962890625%
= 99.999999976716935634613037109375%
Hence, option-B is most suitable answer.
Question 754 Explanation:
Given data,
— Up time=75%
— Down time=25%
— How many times does this file server have to be replicated to give an Availability of at least 99% is=?
Option-A: Here 2 replications, it means down time is 25% equivalent 0.25.
According to 2 replications we have to multiply with 0.25*0.25=0.0625
Availability= 100-6.25%
= 93%
Option-B: Here 4 replications, it means down time is 25% equivalent 0.25.
According to 4 replications we have to multiply with 0.25*0.25*0.25*0.25
= 0.00390625
Availability= 100-0.0390625%
= 99.9609375%
Option-C: Here 8 replications, it means down time is 25% equivalent 0.25.
According to 8 replications we have to multiply with
= 0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25
= 0.0000152587890625
Availability= 100-0.00152587890625%
= 99.99847412109375%
Option-D: Here 16 replications, it means down time is 25% equivalent 0.25.
According to 16 replications we have to multiply with
= 0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25*0.25
= 0.00000000023283064365386962890625
Availability= 100-0.000000023283064365386962890625%
= 99.999999976716935634613037109375%
Hence, option-B is most suitable answer.